1N2809RB datasheet(3/4 Pages) MICROSEMI

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50 Watt Zener Diodes

SCOTTSD A L E DIVISION

1N2804 thru 1N2846B and

1N4557 thru 1N4564B

NOTES:

The JEDEC type numbers shown (B suffix) have a +/- 5% tolerance on nominal zener voltage. The suffix A is used to identify +/-10%

tolerance; no suffix indicates +/-20% tolerance. If tighter tolerance is required, consult factory. Standard polarity units have the anode

connected to the case. Reverse polarity (cathode-to-case) units are available and are indicated by suffix R in the part number.

Zener Voltage (VZ) is measured with junction in thermal equilibrium with 30

oC base temperature. The test currents (IZT) have been selected

so that at nominal voltages the dissipation is a constant 12.5 watts. This results in a nominal junction temperature rise of 18.75

oC .

The zener impedance is derived from the 60 cycle ac voltage, which results when an ac current having an rms value equal to 10% of the dc

zener current (IZT or IZK) is superimposed on IZT or IZK. Zener impedance is measured at 2 points to ensure a sharp knee on the breakdown

curve and to eliminate unstable units. A curve showing the variation of zener impedance vs. zener current for six representative types is

shown in Figure 3. Also see MicroNote 202 for further information.

The values of IZM are calculated for a +/-5% tolerance on nominal zener voltage. Allowance has been made for the rise in zener voltage

above VZT that results from zener impedance and the increase in junction temperature as power dissipation approaches 50 watts. In the

case of individual diodes, IZM is that value of current that results in a dissipation of 50 watts.

GRAPHS AND CIRCUITS

Typical circuit connections for anode-to-case and

cathode-to-case polarities (standard and reverse

polarities, respectively).

Case

Temperature

FIGURE 2

POWER DERATING CURVE

FIGURE GROUP 3

TYPICAL ZENER IMPEDANCE vs. ZENER CURRENT FOR TYPES SHOWN

Microsemi

Scottsdale Division

8700 E. Thomas Rd. PO Box 1390, Scottsdale, AZ 85252 USA, (480) 941-6300, Fax: (480) 947-1503

Page 3

 2003

11-12-2003 REV A

1N2809RB Datasheet(PDF) 3 Page - Microsemi Corporation